Trying to plug in an mp3 player to aux jack in back but no sound. is it even used for that?

Have you tried headphones to see if the sound is even generated.

An easy cheap soloution if this works is to possiblt use exernal speakers in the aux jack.

Just plug the cord into the front of the cd player where it says "AUX" and then plug the other end of the cord into the headphone / line out jack on any ipod or mp3 player then select "AUX" instead of CD and the sound will come through the system

The front panel jacks are Video 3 according to my manual. Aux is on the back panel.

first of all the rca jacks in the back of your radio are for plugging in an amp, not your mp3 player. there should be an auxiliary jack(looks like a headphones jack) in the front of the head unit. if there is no auxiliary jack in the front then you will have to go buy a new head unit with an auxiliary jack.

Hi, I have the Panasonic SA-EN9, and if you plug your mp3 player (I have and ipod) into the auxiliary socket you should be able to play it by pressing the AUX button on the remote provided. 
Hope It Helps :)

You should be able to do that as long as you have the right cable.

Most of the mp3 players have a "mini-stereo" jack (3.5mm) and some car stereos have the same type of jack for "aux" input, and others car stereos have RCA jacks for the "aux" input.

Even if the jacks are not the same type, you can use an adapter cable that converts the mini-stereo jack to an RCA jack. You can find them at many places like Best Buy, Circuit City or Radio Shack.

Depending on the type of car stereo you have, you would normally press the source button to change between the tuner, cd player, aux or whatever you may have connected to the stereo. You may even have a seperate button to press for the "aux" input.

I hope this was helpful to you, if you need more information just ask, and please give more info on the type of mp3 player and the make and model number of the car stereo.

they are out jacks and you need to run the rcas to an amp and then run your speakers off the amp your mp3 player should work when you plug it in the front and press source aux unless the front jack is an out only

Aux input on the back depends if there was a aux button on the front and the brand of deck. If one is there then you dont need Best Buy to do it. removing the deck is not as hard as people make it seem. The best way to remove the deck to check is find a manual for removal; exp: chiltons, hayne or even get it from crutchfield. Be careful though, some decks may have the aux button and a 3.5mm jack in the back but the jack is sometimes used for a remote. So get the mauals for the deck you have and the manual for removal.

Again RCA stereos **** for this factor, cheap transformers, replace the transformer and see if that helps as it seems to be the most problem with most RCA systems I've repaired in the past.

nope, it has it on the back